In the applicant's co-pending application PCT/GB07/000835 a novel and particularly quick apparatus for placing battery plates in a line from a stack of plates is described. The specific embodiment relies on a carousel of vacuum heads. The apparatus works extremely well, but it has a high and expensive component count and requires particularly sophisticated control.
The present invention consists of an apparatus for placing battery plates in a line from a stack of plates including an elevator for receiving a stack of plates and for sequentially elevating the stack to maintain, in use, the uppermost plate in the stack in a datum region lying between two parallel generally horizontal planes and the polarity of vacuum heads arranged in the closed loop for sequentially passing over the elevator with a fixed gap from the upper plane of the datum range for picking up the uppermost plate and subsequently releasing the plate at a release position wherein the apparatus includes an endless horizontal belt having a plurality of spaced perforate portions, which respectively constitute the vacuum heads, a vacuum chamber located adjacent the datum region for acting in a sense to lift the uppermost plate from this stack and the motor for rotating the belt whereby the perforate portions pass sequentially over the vacuum chamber.
This approach has a number of advantages. Firstly the component count is significantly decreased, in particular because the vacuum chamber does not have to move; it is only the endless belt that needs to move. Secondly the application of the vacuum is strictly along the longitudinal axis of the stack, whereas in the aforementioned PCT application, the vacuum sweeps over the plate. Conveniently, the aerodynamic effect of the moving belt is to reduce the pressure immediately above the plate and cause the uppermost plate to separate from the stack, before the vacuum is applied as the perforate portion passes over the vacuum chamber.
Conveniently the vacuum chamber has an open or perforate wall over which the perforate portions pass and, additionally or alternatively, a valve may be provided for determining whether or not the vacuum chamber is at a negative pressure.
There may be at least two elevators spaced in the direction of travel of the belt and a vacuum chamber may be associated with each elevator.
In a particularly convenient construction, the apparatus includes a body around which the belt runs and the body defines two sets of vacuum chambers; the first set including the first mentioned vacuum chamber or chambers and a second set including one or more chambers for providing, with the first set, a continuous vacuum path from the datum region to the release position.
The second set of vacuum chambers may provide a continuous constant vacuum so that plates are held to the belt as they move to the release position. At the release position it is preferred that there is a further switchable vacuum chamber, so that the plate can be actively released, but the release position could be formed simply by an absence of a vacuum chamber at that location.
Although the invention has been defined above, it is to be understood that it includes any inventive combination of the features set out above or in the following description.